1. Field of the Invention
The present invention is concerned with a compression equipment for injecting and molding a workpiece under compression and with an injection compression molding machine.
2. Description of the Related Art
Injection compression molding has been recognized as a preferable method of molding a thin molding of polymeric material with low bowing and distortion. A conventional injection compression molding machine for forming moldings is provided with a stationary die plate on which a stationary mold is secured, a moving die plate to which a moving die is secured, a mold clamping apparatus for moving reciprocally the moving die plate toward the stationary die plate, and compression equipment for further compressing and moving the moving mold until it is in a position at which the mold clamping apparatus makes a small aperture with reference to the stationary mold after filling up with the molten resin.
The compression equipment employed in the above conventional injection compression molding machine is taught in Japanese Utility Model Application Laid-open No. 48-25749 and the Japanese Patent Application Publication No. 36-1477. As set forth in these documents, the moving die plate is moved by a different cylinder from a mold clamping apparatus and a cylinder which moves the moving mold into the moving die plate is provided.
Because the compression equipment is a constructing part of the injection compression molding machine in this prior art, the moving die plate, for example, needs to be modified on a large-scale into a construction provided with the compression equipment when a general injection molding machine performs injection and mold under compression. In other words, these injection molding machines need to be significantly reconfigured in order to inject and mold under compression by various injection molding machines when the mold clamping forces are different, so that the conventional compression equipment can be said that it does not possess generality of the injection molding machine.
An object of this invention is to provide a compression equipment of the injection compression molding which possess the generality of various injection molding machine and injects and molds under compression without significant reconfiguration of the injection molding machine on a large-scale and an injection compression molding machine provided with a compression equipment.